Improvement from discrete to uniform wetting of organic perovskite on ferromagnetic metals through a heterointerface

Zih-En Lin^1*, Shi-Yu Liu¹, Bing-Tsun Wu¹, Ting-Hao Chen¹, Hsuan-Ching Hung¹, Chun-Han Yin¹, Chak-Ming Liu¹, Po-Chun Chang¹, Yu-Chiang Chao¹, Wen-Chin Lin¹

¹Department of Physics, National Taiwan Normal University, Taipei, Taiwan

* Presenter:Zih-En Lin, email:ajectivity@gmail.com

Considerable effort has been expended on the combination of a ferromagnetic layer with a perovskite film for application in light-controlled spintronic devices. However, to achieve such combinations, gaining control over the interface quality and the interaction between the ferromagnetic and perovskite layers is crucial. Studies have observed discrete distributions of organic perovskite (methylammonium
lead bromide, MAPbBr3) films, which self-assemble into nanodiscs, on iron–palladium alloy films. To achieve uniform wetting, we proposed the insertion of an ultrathin heterointerface of an aluminum oxide or graphene layer between perovskite and metal films. Through atomic force microscopy and scanning electron microscopy, we observed that the derived MAPbBr3 coating successfully formed a continuous and dense layer without voids, with its roughness fluctuations being within a few nanometers. Magneto-optical Kerr effect measurement for material characterization revealed that the perovskite films had a negligible capping effect on magnetism. These results provide insight into the
potential technological applications of perovskite/metal heterostructures.

Keywords: perovskite, AlOx, graphene